A notable feature of Turkishphonology is a system of vowel harmony that causes vowels in most words to be either front or back and either rounded or unrounded. Stop consonants have palatal allophones before front vowels and velar allophones before back vowels.

In native Turkic words, the velar consonants /k, ɡ/ are palatalized to [c, ɟ] (similar to Russian) when adjacent to the front vowels /e, i, œ, y/. Similarly, the consonant /l/ is realized as a clear or light [l] next to front vowels (including word finally), and as a velarized [ɫ] (dark l) next to the central and back vowels /a, ɯ, o, u/. These alternations are not indicated orthographically: the same letters ⟨k⟩, ⟨g⟩, and ⟨l⟩ are used for both pronunciations. In foreign borrowings and proper nouns, however, these distinct realizations of /k, ɡ, l/ are contrastive. In particular, [c, ɟ] and clear [l] are sometimes found in conjunction with the vowels [a] and [u]. This pronunciation can be indicated by adding a circumflex accent over the vowel: e.g. gâvur "infidel", mahkûm "condemned", lâzım "necessary".[1]

/ɾ/ is realized as a modal flap [ɾ] intervocalically.[2] At the margins of words, the passage at the alveolar ridge is closed so that it becomes fricated;[2] in addition, it undergoes final devoicing.[2] Thus it is [ɾ̝] word-initially and [ɾ̝̊] word-finally.

/v/ is only pronounced [v] after voiceless consonants, as in cetvel. It is silent before labial consonants, as in sövmek. Elsewhere it is [ʋ].[citation needed]

Voiceless stops are aspirated in initial and medial position.[3]/b, d, d͡ʒ, ɡ, ɟ/ are devoiced to [p, t, t͡ʃ, k, c] word- and morpheme-finally, as well as before a consonant: /edˈmeɟ/ ('to do, to make') is pronounced [etˈmec]. (This is reflected in the orthography, so that it is spelled ⟨etmek⟩). When a vowel is added to nouns ending with postvocalic /ɡ/, it is lenited to ⟨ğ⟩ (see below); this is also reflected in the orthography.[4]

In addition, there is a debatable phoneme, called yumuşak g ('soft g') and written ⟨ğ⟩, which only occurs after a vowel. It is sometimes transcribed /ɰ/. Between back vowels, it may be silent or sound like a bilabial glide. Between front vowels, it is either silent or has a [j] sound (e. g. düğün "wedding, marriage", where the [j] is even mandatory in fast speech to distinguish it from dün (yesterday)), depending on the preceding and following vowels. When not between vowels (that is, word finally and before a consonant), it is generally realized as vowel length, lengthening the preceding vowel, or as a slight [j] if preceded by a front vowel.[5] Historically, and perhaps still for some people or in careful pronunciation, it was a velar approximant[ɰ].[6] Before the loss of this sound, Turkish did not allow vowel sequences in native words, and today the letter ⟨ğ⟩ serves largely to indicate vowel length and vowel sequences where /ɰ/ once occurred.[7] Karl Zimmer and Orhan Orgun[8] transcribe it as /ɣ/.

The vowels of the Turkish language are, in their alphabetical order, ⟨a⟩, ⟨e⟩, ⟨ı⟩, ⟨i⟩, ⟨o⟩, ⟨ö⟩, ⟨u⟩, ⟨ü⟩.[9] There are no diphthongs in Turkish and when two vowels come together, which occurs in some Arabic loanwords, each vowel retains its individual sound.

(/ø/ may also be transcribed as ⟨œ⟩ (as in the vowel chart at right), but has the same mid height as /e/ and /o/.)

Although a central vowel phonetically, /a/ is phonologically a "back" vowel based on its patterning with other back vowels in harmonic processess and the alternation of adjacent consonants (see above). The vowel /e/ plays the role as the "front" analog of /a/.

All vowels but /o a/ have lowered allophones word-finally: [ɪ ʏ ɛ œ ʊ]. In addition, for most people /e/ has an allophone [æ] before a syllable-coda /m n l r z/, so that perende 'somersault' is pronounced [perænˈdɛ]. There are a limited number of words, such as kendi 'self' and hem 'both', which are pronounced with [æ] by some people and with [e] by some others.[10]

With some exceptions, a native Turkish word incorporates either exclusively back vowels (/a ɯ o u/) or exclusively front vowels (/e i ø y/), as, for example, in the words karanlıktaydılar ('they were in the dark') and düşünceliliklerinden ('due to their thoughtfulness'). /o ø/ only occur in the initial syllable.

The Turkish vowel system can be considered as being three-dimensional, where vowels are characterised by three features: front/back, rounded/unrounded, and high/low, resulting in eight possible combinations, each corresponding to one Turkish vowel, as shown in the table.

Vowel harmony of grammatical suffixes is realized through "a chameleon-like quality",[11] meaning that the vowels of suffixes change to harmonize with the vowel of the preceding syllable. According to the changeable vowel, there are two patterns:

twofold (/e/~/a/):[12] Frontality is preserved, that is, /e/ appears following a front vowel and /a/ appears following a back vowel. For example, the locative suffix is -de after front vowels and -da after back vowels. The notation -de2 is shorthand for this pattern.

fourfold (/i/~/y/~/ɯ/~/u/): Both frontality and rounding are preserved. For example, the genitive suffix is -in after unrounded front vowels, -ün after rounded front vowels, -ın after unrounded back vowels, and -un after rounded back vowels. The notation -in4 can be this pattern's shorthand.

The vowel /ø/ does not occur in grammatical suffixes. In the isolated case of /o/ in the verbal progressive suffix -i4yor it is immutable, breaking the vowel harmony such as in yürüyor ('[he/she/it] is walking').

Some examples illustrating the use of vowel harmony in Turkish with the copula-dir4 ('[he/she/it] is'):

Türkiye'dir ('it is Turkey') – with an apostrophe because Türkiye is a proper noun.

gündür ('it is the day')

kapıdır ('it is the door')

paltodur ('it is the coat').

Compound words do not undergo vowel harmony in their constituent words as in bugün ('today'; from bu, 'this', and gün, 'day') and başkent ('capital'; from baş, 'prime', and kent, 'city').

Vowel harmony does not usually apply to loanwords and some invariant and irregular suffixes, such as -ki ('belonging to ...') and -ken ('while ...-ing'). In the suffix -e2bil ('may' or 'can'), only the first vowel undergoes vowel harmony. There are a few native Turkish words that do not have vowel harmony such as anne ('mother'). In such words, suffixes harmonize with the final vowel as in annedir ('she is a mother').

In most words, consonants are neutral or transparent and have no effect on vowel harmony. In borrowed vocabulary, however, back vowel harmony can be interrupted by the presence of a "front" (i.e. coronal or labial) consonant, and in rarer cases, front vowel harmony can be reversed by the presence of a "back" consonant.

noun

dative
case

meaning

type
of l

noun

dative
case

meaning

type
of l

hal

hale

situation

clear

rol

role

role

clear

hal

hale

closed
market

clear

sol

sole

G-note
(music)

clear

sal

sala

raft

dark

sol

sola

left

dark

For example, Arabic and French loanwords containing back vowels may nevertheless end in a clear [l] instead of a velarized [ɫ]. Harmonizing suffixes added to such words contain front vowels.[13] The table on the right gives some examples.

Front-vowel suffixes are also used with many Arabic monosyllables containing ⟨a⟩ followed by two consonants, the second of which is a front consonant: e.g. harfi "letter-acc.", harp/harbi "war/war-acc.". Some combinations of consonants give rise to vowel insertion, and in these cases the epenthetic vowel is also a front vowel: e.g. vakit/vakti "time/time-acc." ( ← وقت waqt), kavil/kavli "agreement/agreement-acc." ( ← قول qawl).[15]

There is a tendency to eliminate these exceptional consonantal effects and to apply vowel harmony more regularly, especially for frequent words and those whose foreign origin is not apparent. For example, the words rahat "comfort" and sanat "art" take back-vowel suffixes, even though they derive from Arabic tāʾ marbūṭa.[16]

Main stress occurs regularly on the last syllable of a word,[17] except for forms including suffixes with inherent stress, adverbs, proper names, and some loanwords (particularly from Italian and Greek) such as masa/ˈmasa/ ('desk'), lokanta/loˈkanta/ ('restaurant'), and iskele/isˈkele/ ('pier'). The lexical exceptions in Turkish stress have been important to linguistic theories of how phonological exceptions should be represented grammatically.[citation needed]

The metrical weight of a syllable in terms of moras has no effect on the placement of stress in the regular pattern. Light (L) syllables in Turkish are open syllables (V or CV) which consist of a single mora while heavy (H) syllables have consonantal codas (VC or CVC) and consist of two moras.

Proper names (of both places and foreign people) follow a different stress pattern, known in the linguistics literature as Sezer stress (after the discoverer of the pattern, Engin Sezer). In this lexical domain, stress occurs on the antepenult if the penult is light and the antepenult is heavy, and otherwise on the penult. The weight of the final syllable is irrelevant.

Penultimate stress:

L'LL

/aˈda.na/

Adana

L'LH

/oˈɾe.ɡon/

Oregon

L'HL

/eˈdiɾ.ne/

Edirne

L'HH

/vaˈʃink.ton/

Vaşington

H'HL

/anˈtal.ja/

Antalya

H'HH

/isˈtan.bul/

İstanbul

'HL

/ˈordu/

Ordu (city)

Antepenultimate in …HLσ words:

'HLL

/ˈan.ka.ɾa/

Ankara

'HLH

/ˈmeɾ.dʒi.mek/

Mercimek

The Sezer stressed form /aˈda.na/ would be expected to have the unattested form */a.daˈna/ under the regular stress pattern. Thus, it can be seen that the regular and the Sezer pattern are contrastive.

The Sezer stress pattern is productive in spite of it being observed on a smaller set of lexical items. Suffixed words that have the regular pattern can shift to the lexical class of placenames (via zero-derivation). When these words are used as placenames, the regular stress pattern shifts to the Sezer pattern. For instance, the word /toɾ.baˈlɯ/torbalı ('with bag') has regular stress in its normal use, but when a placename it has Sezer stress /ˈtoɾ.ba.lɯ/.

The Sezer stress pattern is completely regular, including for loanwords whose source language version has a different stress pattern. That is, source stress is not preserved in Turkish. For example, the English word Arkansas has antepenultimate stress (i.e. /ˈɑr.kən.sɔː/), but the loanword in Turkish has penultimate stress.

One approach to the metrical analysis of the Sezer pattern posits a general disyllabic iambic rhythm that is aligned with the right word edge with a restriction against having a nonfinal foot (or alternately requiring an extrametrical final syllable) and a requirement that heavy syllables carry stress (weight-to-stress). Thus:

(L'L)σ

/(aˈda)na/, /(oˈɾe)ɡon/

nonfinal right-aligned even iamb

(L'H)σ

/(eˈdiɾ)ne/, /(vaˈʃink)ton/

nonfinal right-aligned uneven iamb

(H'H)σ

/(anˈtal)ja/, /(isˈtan)bul/

nonfinal right-aligned heavy iamb

The words with antepenultimate stress have a rhythmic reversal to a trochee to prevent a heavy antepenultimate syllable from not being stressed, that is an illicit *(H'L)σ form:

The regular stress pattern occurs on words with a stem combined with suffixes. Here the stress is consistently word-final and appears to shift rightward away from the stem as suffixes are concatenated.

Words ending with a personal predicative suffix are generally stressed on the preceding syllable. This stress pattern can be useful in disambiguating homographic words containing possessive suffixes or the plural suffix:[18]

ben-im

/ˈbe.nim/

'It's me'

vs.

ben-im

/beˈnim/

'my'

çocuk-lar

/tʃoˈdʒuk.laɾ/

'They are children'

vs.

çocuk-lar

/tʃo.dʒukˈlaɾ/

'(the) children'

Other suffixes which do not take stress are the interrogative and negative suffixes mi and ma, and the adverbial and adjectival suffixes le and ce:

Geldi mi?

Yápma!

bu surétle ('in this way')

Tǘrkçe ('Turkish')

yálnız ('only'; cf. yalníz, 'alone')

On the other hand, the verbal tense/aspect/mood morpheme is usually stressed:

geliyórum

gidérsin

In negated verbs, the stress typically falls on the syllable preceding the negation morpheme:

^Most monosyllabic words ending in orthographic ⟨k⟩, such as çok ('much'), are phonologically /k/, but nearly all polysyllabic nouns with ⟨k⟩ are phonologically /ɡ/. Lewis (2001:10). Proper nouns ending in ⟨k⟩, such as İznik, are equally subject to this phonological process but have invariant orthographic rendering.

^For the terms "twofold" and "fourfold", as well as the superscript notation, see Lewis (1953:21–22). He later preferred to omit the superscripts, on the grounds that "there is no need for this once the principle has been grasped" Lewis (2001:18).

Zimmer, Karl; Orgun, Orhan (1999), "Turkish", Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press, pp. 154–158, ISBN0-521-65236-7